Bug#35710213: mysql server 8.1.0 failed at Item_field::used_tables

The original fix for this problem caused a regression in test
i_main.fulltext-bug17865492 in --ps-protocol mode.
The reason for this is a missing implementation of the function
update_used_tables() for the class Item_func_match. When rebuilding
used tables information and item properties, the argument "against" is
never considered. This means that for execution of prepared statements,
the Item_func_match expression is no longer considered to be an
aggregated expression, and the optimizer will pick the wrong
substitution field when setting up an intermediate temporary table.

The fix for this problem is to implement update_used_tables() for this
class, and explicitly add used tables information and properties for
the "against" argument.

Change-Id: Ic3a4c61ae6706a772a2c3616927a08751a3ade42

Author: roylyseng

sql/item_func.cc

@@ -7630,6 +7630,13 @@ bool Item_func_match::fix_fields(THD *thd, Item **ref) {
                                             arg_count, 0);
 }
 
+void Item_func_match::update_used_tables() {
+  Item_func::update_used_tables();
+  against->update_used_tables();
+  used_tables_cache |= against->used_tables();
+  add_accum_properties(against);
+}
+
 bool Item_func_match::fix_index(const THD *thd) {
   TABLE *table;
   uint ft_to_key[MAX_KEY], ft_cnt[MAX_KEY], fts = 0, keynr;

sql/item_func.h

@@ -3457,6 +3457,7 @@ class Item_func_match final : public Item_real_func {
   enum Functype functype() const override { return FT_FUNC; }
   const char *func_name() const override { return "match"; }
   bool fix_fields(THD *thd, Item **ref) override;
+  void update_used_tables() override;
   bool eq(const Item *, bool binary_cmp) const override;
   /* The following should be safe, even if we compare doubles */
   longlong val_int() override {